Sir Joseph Williamson’s Mathematical School (SJWMS) is an all boys’ grammar school (which accepts girls in the Sixth Form) with academy status in Rochester, Kent, also referred to either as Rochester Math or The Math School.

The school was founded by the statesman Sir Joseph Williamson (1633-1701),  Lord of the nearby Manor of Cobham, Kent, who in his will bequeathed £5,000 to set up the school. The school was termed a mathematical school because it specialised in teaching navigation and mathematics to the sons of Freemen of the City of Rochester, the Chatham Naval Dockyard being nearby.

The first building was in 1708 when a “school house” was built in part of the filled up moat outside the city walls.

In 1840 additional rooms were built and in both 1882 and 1893 additions were made.

 In the late 1960s the buildings were demolished and the school relocated to the current location in  Maidstone Road.